Cap comprising a release indicator for a container

ABSTRACT

The invention relates to a cap for an airtight container such as a glass or plastic bottle or jar, which cap is suitable to be placed releasably in a closing position on a neck of the container, wherein the cap is provided with visual indicating means for indicating that the cap is no longer in the closing position, wherein the indicating means are adapted to be brought into an active state when the cap is arranged on the neck of the container and to be brought into the indicating state when the cap is removed. These measures have the result that the indicator only becomes active, i.e. enters into the indicating state, when this state is preceded by an active state. The fact that it has to be successively subjected to two different states makes it easier to find such an indicator; use can after all be made of indicating means which are not normally active, for instance in the stored situation, and which are only activated by arranging thereof on the neck of the container.

[0001] The invention relates to a cap for an airtight container such as a glass or plastic bottle or jar, which cap is suitable to be placed releasably in a closing position on a neck of the container, wherein the cap is provided with visual indicating means for indicating that the cap is no longer in the closing position.

[0002] In the prior art use is herein made of a collar which is arranged on the underside of the cap and which prevents the cap coming loose. It is of course possible to unscrew the cap, although this is only possible when the collar is broken. This is clearly visible to the user.

[0003] There are nevertheless drawbacks associated with such collars; they interfere with screwing of the cap onto the neck of a bottle because the collar is pulled out of alignment.

[0004] Such a collar moreover makes unscrewing of the cap difficult for the consumer.

[0005] These problems have resulted in research into another type of indicator. Envisaged here is a cap provided with an internal indicator which reacts when the cap is opened by for instance changing colour as a result of the entry of oxygen or nitrogen.

[0006] Such caps cannot be manufactured in practice, or hardly so. Such indicators must after all be stored after manufacture in a nitrogen-free or oxygen-free environment before being arranged on the bottle. Another problem is the difficulty of finding an indicator which does not react to the presence of the gases or liquids normally present in the containers, such as carbon dioxide and water.

[0007] In order to obviate these problems the present invention provides such a cap, wherein the indicating means are adapted to be brought into an active state when the cap is arranged on the neck of the container and to be brought into the indicating state when the cap is removed.

[0008] These measures have the result that the indicator only becomes active, i.e. enters into the indicating state, when this state is preceded by an active state. The fact that it has to be successively subjected to two different states makes it easier to find such an indicator; use can after all be made of indicating means which are not normally active, for instance in the stored situation, and which are only activated by arranging thereof on the neck of the container.

[0009] According to a first preferred embodiment the indicating means are adapted to be brought into the active state when the cap is displaced relative to the neck of the container.

[0010] Although it is possible in principle to detect the arranging of the cap on the bottle or jar in other manner, for instance by the presence of temperature, degree of humidity and the like, the displacement of the cap is found to be an attractive method of indicating the arrangement of the cap; a movement takes place with which it is possible to perform a mechanical action.

[0011] According to a second preferred embodiment the indicating means therefore comprise a mechanical connection which is adapted to be broken when the cap is placed on the neck of the container.

[0012] The indicating means can for instance comprise an indicator which is enclosed in an envelope, wherein the envelope is broken during arranging of the cap on the bottle or jar. The envelope is then still held fixedly however due to the presence of the upper edge of the neck of the bottle, so that only when the cap is loosened is the envelope no longer held fast, and the environment in the form of nitrogen or oxygen is given the opportunity to reach the indicator.

[0013] According to another preferred embodiment the mechanical connection is formed by a limp element which is fixedly attached to the cap on two sides and which is provided with a weakened portion at the position where the limp element makes contact with a component of the container when the cap is arranged on the container, and that the limp element is held fast at the weakened portion by the clamping between the cap and the neck of the container.

[0014] This measure also has the consequence that, when the cap is screwed on, the weakened portion of the limp element is destroyed, but that the limp element is held fast between the upper edge of the neck of the container and the cap and, as soon as the cap is unscrewed slightly, the limp element drops downward.

[0015] Other attractive preferred embodiments are stated in the remaining sub-claims.

[0016] The present invention will be elucidated hereinbelow with reference to the annexed figures, in which:

[0017] FIGS. 1A-1C show partly broken-away, perspective views of a first embodiment of the invention at different stages; and

[0018] FIGS. 2A-2C show partly broken-away, perspective views of a second embodiment of the invention at different stages.

[0019] The invention is applicable in the first place to bottles with optionally carbonated soft drinks, beer and so on, but is also applicable to bottles with a different content, and to for instance glass jars which are closed by a lid.

[0020] The invention is elucidated in the following with reference to a bottle. It will be apparent that the same embodiment can also apply to glass jars.

[0021] Drawn in FIG. 1 is a cap 1 which is manufactured for instance from plastic. Cap 1 is provided on the inner side of its skirt in the usual manner with a screw thread 2. Cap 1 can hereby be screwed onto neck 6 of a bottle. It is however not per se necessary that use be made of a screw-cap. The invention is also applicable to for instance caps arranged by means of a clamp connection or otherwise on the neck of a bottle; the invention is even applicable to crown caps, although here the use of the invention requires special provisions in respect of the visibility of the breaking of the seal.

[0022] Assuming that the cap is made from coloured plastic, a transparent window 3 is arranged in the top surface of the cap. The transparent window 3 gives a visual indication of the state of an indicator 5 arranged in an envelope 4 under window 3. Envelope 4 is for instance manufactured from a plastic film, which plastic film can be perforated by the upper part of the neck of a bottle when cap 1 is screwed onto such a bottle neck.

[0023] The indicator is formed by a substance which changes colour upon entry of a gas or a liquid normally to be found in the bottle. Assuming that the content of the bottle is formed by a soft drink, it is conceivable that an indicator is chosen which changes colour upon entry of carbon dioxide or water vapour and so on.

[0024] The colour change of indicator 5 can then be observed through the window 3.

[0025] It is also conceivable for the combination of envelope 4 and indicator 5 to be received in the “liner” which is usually present against the underside of the upper wall of a cap and which serves to provide adequate sealing.

[0026] This liner is deemed as being arranged in cap 1 in the embodiment now being described.

[0027]FIG. 1B shows how envelope 4 of indicator 5 comes into contact with the upper edge 7 of the neck 6 of a bottle. This upper edge 7 will herein cause damage to envelope 4, whereby this latter becomes permeable for gas and liquid at the position of the point of contact between the top side of bottle neck 6 and envelope 4.

[0028] When cap 1 is subsequently unscrewed, the part of envelope 4 damaged by the upper edge of the neck 6 of the bottle will be released. Such a situation is drawn in FIG. 1C.

[0029] It is conceivable for the indicator 5 in question to undergo a distinct colour change, for instance from blue to red. In order to accentuate this colour change it is possible for a coloured foil to be arranged under transparent window 3, into which foil is for instance recessed a text. If this foil is for instance blue, the relevant text will become visible in red letters on a blue background when the indicator changes colour to red.

[0030] In the embodiment shown in FIG. 2 a strip 8 of a flexible plastic is arranged on the underside of the top surface of cap 1. It is noted here that cap 1 is manufactured integrally from transparent plastic. It is otherwise also possible in this embodiment to apply a transparent window 3 in an otherwise coloured cap, just as it is possible to apply a wholly transparent cap in the first embodiment.

[0031] Strip 8 is made of easily tearable material and preferably fixed against the body of cap 1 under a slight mechanical tension on either side at the position of the point of contact with the upper part of the neck of the bottle.

[0032] As shown in FIG. 2B, when the cap is screwed onto the bottle the upper part 7 of the neck 6 of the bottle will make contact with strip 8, whereby the attachment of strip 8 on one side is destroyed. Strip 8 will however remain clamped fixedly on the side in question between the upper part 7 of the neck of the bottle and cap 1. When cap 1 is subsequently unscrewed, strip 8 will come loose as a result of its mechanical tension and hang downward. It is conceivable that the downward hanging of strip 8 is visible from outside. It is also possible here that due to the strip 8 falling away from the top side of cap 1 a text becomes visible by for instance integrating in cap 1 a foil in which are recessed the letters of the text. In the normal situation these letters are covered by strip 8, but the letters become visible when strip 8 falls away.

[0033] Here also the indicating means can be integrated into the liner, but can also be arranged separately under the liner. 

1. Cap for an airtight container such as a glass or plastic bottle or jar, which cap is suitable to be placed releasably in a closing position on a neck of the container, wherein the cap is provided with visual indicating means for indicating that the cap is no longer in the closing position, characterized in that the indicating means are adapted to be brought into an active state when the cap is arranged on the neck of the container and to be brought into the indicating state when the cap is removed.
 2. Cap as claimed in claim 1, characterized in that the indicating means are adapted to be brought into the active state when the cap is displaced relative to the neck of the container.
 3. Cap as claimed in claim 2, characterized in that the indicating means comprise a mechanical connection which is adapted to be broken when the cap is placed on the neck of the container.
 4. Cap as claimed in claim 3, characterized in that the mechanical connection is arranged on the inner side of the cap, and that it is adapted to be broken by the upper edge of the neck of the container.
 5. Cap as claimed in claim 3, characterized in that the mechanical connection is arranged on the underside of the skirt of the cap, and that it is adapted to be broken through by a collar extending on the outside of the neck of the container.
 6. Cap as claimed in claim 3, 4 or 5, characterized in that the mechanical connection is formed by a limp element which is fixedly attached to the cap on two sides and which is provided with a weakened portion at the position where the limp element makes contact with a component of the container when the cap is arranged on the container, and that the limp element is held fast at the weakened portion by the clamping between the cap and the neck of the container.
 7. Cap as claimed in claim 6, characterized in that the limp element is arranged under mechanical tension between its two attachment positions.
 8. Cap as claimed in claim 3, 4 or 5, characterized in that the mechanical connection is formed by a seal of an envelope of an indicator, which seal is arranged at the position where it makes contact with a component of the container when the cap is arranged on the container, and that the component of the container covers the broken seal when the cap remains fastened on the container.
 9. Cap as claimed in claim 8, characterized in that the indicator is adapted to change colour when it comes into contact with a gas or vapour present in the container.
 10. Cap as claimed in claim 9, characterized in that the container is a soft drink bottle and that the indicator is adapted to change colour when it comes into contact with carbon dioxide.
 11. Cap as claimed in any of the foregoing claims, characterized in that the cap is at least provided with a transparent window which is placed to show the indicator from a normal angle of view.
 12. Cap as claimed in claim 11, characterized in that the window is provided with a text which is visible when the indicator changes colour.
 13. Cap as claimed in any of the claims 8-12, characterized in that the indicator is irreversible.
 14. Cap as claimed in any of the foregoing claims, characterized in that the indicating means are arranged in a liner for placing in the cap. 